The ‘Multiple Nuclei Model’ was given by C.D Harris and Edward L. Ullman in 1945.It was written on a article named ‘The Nature of Cities’.

1. A PRESENTATION ABOUT
“ MULTIPLE NUCLEI MODEL”
 Prepared By-
 Shah Mohammad Atikul Haque
 Department of Urban and Regional Planning
 Batch:14th
 Roll:1884

2. C.D Harris Edward L. Ullman
The ‘Multiple Nuclei Model’ was given by C.D Harris and Edward L. Ullman in
1945.It was written on a article named ‘The Nature of Cities’.
Basic Concept:
The model describes the layout of a city. It says that even though a city may have
began with a Central Business District, or CBD, other smaller CBD's develop on the
outskirts of the city near the more valuable housing areas to allow shorter
commutes from the outskirts of the city. This creates nodes or nuclei in other parts
of the city besides the CBD thus the name multiple nuclei model.

3. The theory is based upon the notion that the cities
have an essentially cellular structure, in which
distinctive types of land use have developed around
certain growing points, or “nuclei” within the urban
area.It is suggested by this model that, the city have a
cellular structure and the
growth of following centers –

4. The nuclei have been encouraged by four factors,
which the distribution of human activities within a city
in a varies ways. These factors are:
1.The location of CBD.
2.Concentration of a certain working group.
3.The close juxtaposition of harmful activities
4.Rent of the most desirable site.
Effects of multiple nuclei on Industry
As multiple nuclei's develop transportation hubs such as
airports are constructed, these transportation hubs allow
industries to be constructed with cheap transportation costs.
These Transportation Hubs can also create noise pollution and
lower land values so land becomes cheap. Hotels are also
constructed near airports because people who travel tend to
want to stay closeby to the airport or source of travel. Housing
develops in wedges and gets more expensive the farther from
the CBD. (Swanson 360-364)

5. Reasons of the model
 The theory was formed based on the idea that
people have greater movement due to increased
car ownership. This increase of movement allows
for the specialization of regional centers (e.g. heavy
industry, business park, Retail Areas). The model is
suitable for the big and expanding cities. The
number of nuclei, around which the city expands,
depends upon the situational as well as historical
factors. Multiple nuclei develop because:
 Certain industrial activities require transportation
facilities e.g. ports, railway stations etc to lower
transportation costs.
 Certain activities tend to stay apart e.g. residential
zoning and airports etc.
 Certain activities are found together to their mutual
advantage e.g. University, bookstore, coffee shops,
etc.

6. Assumptions
The internal geography of cities owes
much peculiarities of their individual
sites.
Well-drained and wooded terrain often
favors the development of a high-class
residential area.
Heavy industry may be attracted by a
flat, ill-drained area, provided that
suitable transport facilities are
available and that is kind of industry is
present in a particular city.

7. It shows the history of individual cities
and their urban development.
Land is Flat
Even Distribution of Resources
Even Distribution of people in
Residential areas
Even Transportation Costs

8. Criticisms
Negligence of height of buildings.
 Each zone displays a significant degree
of internal heterogeneity and not
homogeneity.
Unawareness of inertia forces.
No consideration of influence of physical
relief and government policy.
The concepts may not be totally
applicable to oriental cities with different
cultural, economic and political
backgrounds.

9. The model is not based on any
particular city.
It has a very weak spatial rule – in that
it doesn’t provide a clear picture.
The model cannot produce a simple
model of urban structure.

10. Thank You